Survey and extensions of manufacturing models in two-stage flexible flow shops with dedicated machines

This study considers the manufacturing environments in which m+1 machines are configured as two-stage flexible flow shops with dedicated machines (F2DM). The F2DM scheduling problems arise naturally from practical production and fabrication systems, and they are classified into two categories, whose machine settings are antithetical to each other. In model 1, a single common bottleneck machine is installed at stage 1 and m parallel dedicated machines comprise stage 2. The second model has the m dedicated machines at stage 1 and the bottleneck machine at stage 2. Categorizing the literature according to the performance metrics, we survey the existing research results of the two models and propose several new solution procedures with improved computational complexity. The complexity results are summarized, and suggestions are made for future research.